The present invention relates to a clutch cover assembly used in a friction clutch of a diaphragm spring type for automobiles and others.
Generally, in such a clutch, a pair of wire rings are disposed at both sides of a diaphragm spring for forcing a pressure plate so that the wire rings may form fulcrums of the diaphragm spring. The wire rings are supported by tabs or projections provided at an inner periphery of a clutch cover. However, the projections are extended through openings, which are circumferentially enlarged portions of radial slits, in the diaphragm spring toward the pressure plate, and thus, there are circumferential spaces between the side edges of the projections and the side edges of the openings. Therefore, in the conventional structure, it is impossible to prevent the rotation of the diaphragm spring relative to the clutch cover, resulting in following disadvantages. Namely, the clutch cover rotates together with a flywheel of an engine, and the diaphragm spring, generally, rotates together with the clutch cover. However, when seizure occurs between the inner peripheral portions and a release bearing which is employed for operating the spring, the release bearing prevents or restricts the rotation of the diaphragm spring, so that the diaphragm spring rotates through a length corresponding to said space with respect to the clutch cover, and thus, the side edges of the projections collide with the side edges of the openings in the diaphragm spring. Therefore, dislocation or distorsion occurs at the wire rings and the diaphragm spring, and thus, the diaphragm spring can not operates smoothly, resulting in deviation of an operating characteristic of the clutch.
Accordingly, it is an object of the invention to provide an improved structure, overcoming the above-noted disadvantages, in which a wire ring prevents a relative rotation of a diaphragm spring and a clutch cover.
According to the present invention, a clutch cover assembly comprises a pressure plate; a diaphragm spring; a clutch cover; a release mechanism and a pair of wire rings forming fulcrums for the diaphragm spring; and is characterized in that; said clutch cover is provided at the inner periphery with circumferentially spaced projections, which are bent and extended through openings in the diaphragm spring toward the pressure plate, said wire rings are supported from the inner peripheral sides and the sides opposite to the diaphragm spring by said projections, the wire ring is provided with a cut and an end portion which is bent and inserted without a play into a circumferential space between a side edge of the opening in the diaphragm spring and a side edge of the projection, so that said bent end portion may prevent rotation of the diaphragm spring relative to the clutch cover.
Other and further objects, features and advantages of the invention will appear more fully from the following description of the preferrred embodiments of the invention.